How to read prescription?

On a typical prescription, you will see two sets of rows. Most of the time, the top portion is for your OD or right eye while the bottom portion is for your OS or left eye.

For Distance correction, there should always be a value under Sphere, and most of the time it is negative. Its abbreviation is 'D.V.' which stands for Distance Vision.

For Reading-only correction, there should always be a value under sphere, and most of the time it is positive. If there is a value under Near Vision (N.V., N.V.O.) then enter the power in the BOTTOM half of the form and leave the ADD power blank or ("0.00").

For astigmatism correction, please note that that Cylinder (CYL) and Axis are always provided together. For any value of Cylinder there should always be a value for Axis. Some doctors use positive (+) cylinder and some use negative (-). There is a big difference between the two, so please pay close attention to the positive and negative signs. If you don't have astigmatism correction, doctors might just leave it blank or simply SPH or DS which means Sphere or Diopter Sphere. Axis should be from 1-180 degrees, if you see a value like '5' under axis, this is also the same as '005' or '5 degrees'. It should always be a whole number and there should be no decimal point on the axis.

For Bifocals and Progressive lenses, please check with your eye doctor whether the Addition is for Bifocals or Progressive. Most of the time, compared to the Bifocal Addition, the Addition of the Progressive is higher by 0.25, so please verify. A PAL note written on the prescription is an indication that your prescription is for Progressive; only one ADD means the addition for the Left and Right eyes are the same. Please be advised that we process a minimum of +1.00 and maximum of +3.00 for Addition powers.

Eye Doctors will sometimes leave out the decimal point on the Sphere, Cylinder and Addition. For example, -25 or +175, this is understood -0.25 and +1.75.

It is very important to pay close attention to plus and minus signs as this will greatly affect the lens. If there is anything on the prescription you are not familiar with, please call our Customer Service and we will be happy to assist you.

Prescription will generally be laid out something like this:

Sph

Cyl

Axis

Add

Right

-1.50

-1.00

128

+2.5

Left

-1.25

-0.50

90

+1.5

Sph

Cyl

Axis

Add

Right

-1.50

-1.00

128

+2.5

Left

-1.25

-0.50

90

+1.5

Right

Sph

Cyl

Axis

Prism

Base

Sph

Cyl

Axis

Prism

Base

Left

-1.50

-1.00

128

Distance

-1.25

-0.50

90

+2.5<

Near

+1.5

Some Prescription Samples as Follows:

Sample 1

Sample 2

Sample 3

Sample 4

Sample 5

Abbreviation and Measurements Translate

OD (Oculus Dexter) means right eye,

OS (Oculus Sinister) means left eye.

The Spherical (SPH) correction is for near (-) or far (+) sightedness and PL here means Zero.

The Cylinder and Axis is for astigmatism, Meaning that the eyeball is not exactly Spherical, but slightly oblong, or football shaped. The axis is an angle, from 1 to 180 degrees.

If you have no astigmatism, don't write The Cylinder and Axis.

If the optometrist wrote SPH in the Cylinder space here it means Zero, and consequently no Axis. The Add part is mostly for the over 40 group and is for bifocal reading/near correction.

If you have a prescription for multifocal glasses but want to order a single vision here , just leave off the ADD part which is for the bottom near or reading correction of the bifocal.

pupillary distance (PD)

PD for right eye PD for left eye

Near Vision PD

Sometimes a prescription has two numbers, such as PD 65/62, usually written on a bi-focal prescription. Here 65 is your distance vision PD, which is to be entered in our forms. While 62 is the reading or near vision PD, which is used only if you are ordering a pair of plain reading glasses.

PD

The PD or Pupillary Distance is the distance between your two eyes, the center of one pupil to the center of the other, in Millimeters. Unfortunately most optometrists leave this necessary measurement off from your prescription, but you can measure this yourself.

You can measure this yourself in a mirror (not very accurate and not generally recommended) or have a friend measure it for you by holding a ruler just under the pupils of your eyes and measuring the distance center to center. You should be looking straight forward fixing your focus at a distant object and not at the person measuring you.

Average is about 62mm, and most, 97% or so, falls within 54 to 74 range. If you are coming up with a number outside of this range consider that you might be making a measurement mistake. Do NOT just guess, or assume you‘re just an average 62, and DO NOT measure your old glasses to try to come with this number.

PD = Mono R +Mono L

Occasionally a PD is written as, for example, 32/34.5 which are the measurements from the center of the nose to either eye, and your PD is the sum of the two, 32+34.5=66.5 (Mono R +Mono L = PD) and you can enter this as 66 or 67. It does not really matter.

It does not matter if you are off by a millimeter or two, but try to be as accurate as you can especially for progressive prescription glasses.

You should also be able to get your PD from your previous eyeglass supplier, this figure does not expire with age, they have to give it to you by federal law as well as your full prescription, and it is your property.